Efficacy of metformin on ovulation induction in Asian women with polycystic ovary syndrome

The effects of omega-3 fatty acids and vitamin E co-supplementation on gene expression of lipoprotein(a) and oxidized low-density lipoprotein, lipid profiles and biomarkers of oxidative stress in patients with polycystic ovary syndrome

This study was conducted to determine the effects of omega-3 fatty acids and vitamin E co-supplementation on gene expression of lipoprotein(a) (Lp[a]) and oxidized low-density lipoprotein (Ox-LDL), lipid profiles and biomarkers of oxidative stress in women with polycystic ovary syndrome (PCOS). This randomized double-blind, placebo-controlled trial was done on 68 women diagnosed with PCOS according to the Rotterdam criteria aged 18-40 years old. Participants were randomly assigned into two groups to receive either 1000 mg omega-3 fatty acids from flaxseed oil containing 400 mg α-Linolenic acid plus 400 IU vitamin E supplements (n = 34) or placebo (n = 34) for 12 weeks. Lp(a) and Ox-LDL mRNA levels were quantified in peripheral blood mononuclear cells of PCOS women with RT-PCR method. Lipid profiles and biomarkers of oxidative stress were quantified at the beginning of the study and after 12-week intervention. Quantitative results of RT-PCR demonstrated that compared with the placebo, omega-3 fatty acids and vitamin E co-supplementation downregulated expressed levels of Lp(a) mRNA (P < 0.001) and Ox-LDL mRNA (P < 0.001) in peripheral blood mononuclear cells of women with PCOS. In addition, compared to the placebo group, omega-3 fatty acids and vitamin E co-supplementation resulted in a significant decrease in serum triglycerides (-22.1 ± 22.3 vs. +7.7 ± 23.6 mg/dL, P < 0.001), VLDL- (-4.4 ± 4.5 vs. +1.5 ± 4.7 mg/dL, P < 0.001), total- (-20.3 ± 16.6 vs. +12.2 ± 26.1 mg/dL, P < 0.001), LDL- (-16.7 ± 15.3 vs. +11.9 ± 26.1 mg/dL, P < 0.001) and total-/HDL-cholesterol (-0.5 ± 0.6 vs. +0.4 ± 0.8, P < 0.001). There were a significant increase in plasma total antioxidant capacity (+89.4 ± 108.9 vs. +5.9 ± 116.2 mmol/L, P = 0.003) and a significant decrease in malondialdehyde levels (-0.3 ± 0.4 vs. -0.008 ± 0.6 μmol/L, P = 0.01) by combined omega-3 fatty acids and vitamin E intake compared with the placebo group. Overall, omega-3 fatty acids and vitamin E co-supplementation for 12 weeks in PCOS women significantly improved gene expression of Lp(a) and Ox-LDL, lipid profiles and biomarkers of oxidative stress.

The role of metformin in polycystic ovary syndrome: a systematic review

This meta-analysis evaluated the effectiveness of metformin in subfertile women with polycystic ovary syndrome (PCOS). Only randomized trials investigating the effectiveness of metformin and PCOS definition consistent with the Rotterdam consensus criteria, were eligible. Primary outcome was live birth rate. A literature search identified 27 trials. In therapy naïve women, we found no evidence of a difference in live birth rate when comparing metformin with clomifene citrate (CC) [relative risks (RR) 0.73; 95% confidence interval (CI) 0.51-1.1] or comparing metformin plus CC with CC (RR 1.0; 95% CI 0.82-1.3). In CC-resistant women, metformin plus CC led to higher live birth rates than CC alone (RR 6.4; 95% CI 1.2-35); metformin also led to higher live birth rates than laparoscopic ovarian drilling (LOD) (RR 1.6; 95% CI 1.1-2.5). We found no evidence for a positive effect of metformin on live birth when added to LOD (RR 1.3; 95% CI 0.39-4.0) or FSH (RR 1.6; 95% CI 0.95-2.9), or when co-administered in IVF (RR 1.5; 95% CI 0.92-2.5). In IVF, metformin led to fewer cases of ovarian hyperstimulation syndrome (OHSS) (RR 0.33; 95% CI 0.13-0.80). This meta-analysis demonstrates that CC is still first choice therapy for women with therapy naïve PCOS. In CC-resistant women, the combination of CC plus metformin is the preferred treatment option before starting with LOD or FSH. At present, there is no evidence of an improvement in live birth when adding metformin to LOD or FSH. In IVF, metformin leads to a reduced risk of OHSS.

Metformin prevents embryonic resorption induced by hyperandrogenisation with dehydroepiandrosterone in mice

The present study examined the mechanism by which metformin prevents dehydroepiandrosterone (DHEA)-induced embryonic resorption in mice. Treatment with DHEA (6 mg/100 g bodyweight, 24 and 48 h post implantation) induced 88 +/- 1 % embryonic resorption and the diminution of both serum oestradiol (E) and progesterone (P) levels. However, when metformin (50 mg/kg bodyweight) was given together with DHEA, embryo resorption (43 +/- 3% v. 35 +/- 5% in controls) and both serum E and P levels were not significantly different from controls. Glucose and insulin levels were increased in the DHEA-treated mice but when metformin was administered together with DHEA these parameters were similar to control values. Treatment with DHEA increased ovarian oxidative stress and diminished uterine nitric oxide synthase (NOS) activity; however, when metformin was administered together with DHEA, both ovarian oxidative stress and uterine NOS activity were not different from controls. Metformin treatment did not modify the percentage of CD4(+) and CD8(+) T cells from both axillar and retroperitoneal lymph nodes but prevented the increase of serum tumour necrosis factor +/- produced in DHEA-treated mice. These results show that metformin acts in DHEA-induced embryonic resorption in mice by modulating endocrine parameters, ovarian oxidative stress and uterine NOS activity.